The only ‘catch’ you may stumble on is that I’m checking against the post type of post_type_shows – just change that as you need to.

Voila! Instant hashtags.

Oh and if you’re wondering why I didn’t put in a check for “Is Jetpack active…” the reason is that this is adding a post meta, and doesn’t actually depend on Jetpack being active at all. Will it ‘clutter up’ your database if Jetpack isn’t active? Yes. But it won’t break your site so it’s safe enough for me.